You aren't someone's bosd if you don't have authority to fire them. I've dealt with people like that. You explain something to them 5 times and they still don

You aren't someone's bosd if you don't have authority to fire them. I've dealt with people like that. You explain something to them 5 times and they still don't get it. Some people just don't have the talent. The previous lead probably didn't notice or care. Did you speak with your bosses about replacing them? Even if the team lead is just being narrowminded, those two devs would be better off working with someone else.